Re: Ada/UNIX(tm) and the NAME function

[jws@hpcljws.HP.COM (John Stafford)]

Relative names:

   My interpretation of NAME is that simply attaching the output of
   getcwd to a relative name does not meet the specification that "If an
   environment allows alternative specification of the name ...  , the
   string returned by the function should correspond to the full
   specification of the name".  As noted, on systems with "symbolic
   links" and "hidden directories" and the like, it really feels like
   such should be "removed" in order to return "the full specification".
   Perhaps I am over-reading the RM, I had thought that the spirit of an
   RM specification was to be as precise as possible.  It is at least
   clear that precision is currently not present when using NAME on
   UNIX.

   I can't imagine any sane program comparing the NAMEs of files,
   although certainly an Ada product should document what its version of
   NAME does lest somebody think they can reliably do such a thing.

   I would like to see NAME return the same thing for a given file no
   matter what path I used to open the file (except if such is not
   possible, as in the case of hard links).  But I suspect I am asking
   for more than what is required.

   If I open

      foo
      ./foo
      ./././././././foo

   is it reasonable that the result returned by NAME should be different
   in each case?

Other issues:

   I still don't know what one should do if the file can be opened but
   the name cannot be determined (e.g.  due to lack of parent directory
   access permission).

   I also am not "Ada knowledgeable" enough to know that it is OK for
   routines which the RM defines as able to raise some exceptions to
   raise others as well.  I would genuinely appreciate references to why
   this is OK (at first glance it would seem to me to make an
   implementation of Ada non-conformant if use of NAME could raise
   NAME_ERROR).